In an existing water purification apparatus, polypropylene (PP) cotton, activated carbon and the like are adopted as a pre-filter cartridge, a reverse osmosis (RO) filter cartridge is connected in series, and a water system in which multi-stage filter cartridges are connected performs water purification. The service life of the multi-stage filter cartridges is inconsistent, so a consumer needs to replace three to five stages of filter cartridges. As it is required to buy the filter cartridges frequently and replace the filter cartridges by a professional installer, the consumer has bad experience, and the comprehensive cost is high.
In the assembly process, the installer is not only required to clean the filter cartridge, but also required to detect water quality of tap water so as to set the service life of different filter cartridges, so the assembly time is long and the labor cost is high.